Motor vehicles with automatic transmissions are already known from the state of the art. It is more and more often the case that these automobiles are available with a start-stop function.
Before this backdrop, conventional automatic transmissions that have a mechanically driven oil pump are equipped with a start-stop function.
In order to allow a faster and more comfortable start-up, the shilling elements needed for the start-up have to be supplied with hydraulic oil during the starting phase of the engine.
For this purpose, it is especially possible to employ a hydraulic reservoir that is filled via the main transmission pump and that releases its volume of stored oil whenever needed.
German laid-open document DE 10 2009 050 847 A1 discloses a device with which an amount of fluid that can be stored in a reservoir is released in a pulsed manner.
This device makes use of a valve array consisting of an electromagnetic seat valve and a non-return valve. This valve array is aimed at providing leak-proof regulation of a piston position as well as achieving a pulsed release of an amount of fluid stored in a reservoir.
A drawback here is the fact that a directly regulated seat valve is employed.
As soon as high volume flows are needed, the seat valve has to have appropriately large flow cross sections. This gives rise to high shifting forces and to a large and expensive magnet system.
High volume flows occur, particularly when the valve array is used in an automatic transmission for purposes of implementing a start-stop function.
Consequently, the prior-art valve array is not very suitable for use in an automatic transmission for purposes of implementing a start-stop function since it would require a great deal of installation space and entail high costs.